The Collaborative International Dictionary of English v.0.48:

Cloister \Clois"ter\, n. [OF. cloistre, F. clo[^i]tre, L.
   claustrum, pl. claustra, bar, bolt, bounds, fr. claudere,
   clausum, to close. See Close, v. t., and cf. Claustral.]
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   1. An inclosed place. [Obs.] --Chaucer.
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   2. A covered passage or ambulatory on one side of a court;
      (pl.) the series of such passages on the different sides
      of any court, esp. that of a monastery or a college.
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            But let my due feet never fail
            To walk the studious cloister's pale. --Milton.
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   3. A monastic establishment; a place for retirement from the
      world for religious duties.
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            Fitter for a cloister than a crown.   --Daniel.
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   Cloister garth (Arch.), the garden or open part of a court
      inclosed by the cloisters.

   Syn: Cloister, Monastery, Nunnery, Convent, Abbey,
        Priory.

   Usage: Cloister and convent are generic terms, and denote a
          place of seclusion from the world for persons who
          devote their lives to religious purposes. They differ
          is that the distinctive idea of cloister is that of
          seclusion from the world, that of convent, community
          of living. Both terms denote houses for recluses of
          either sex. A cloister or convent for monks is called
          a monastery; for nuns, a nunnery. An abbey is a
          convent or monastic institution governed by an abbot
          or an abbess; a priory is one governed by a prior or a
          prioress, and is usually affiliated to an abbey.
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